Various arrangements to generate trigger pulses, and particularly to generate ignition, or fuel injection control pulses have been proposed. One such arrangement is shown in German Patent Publication DT-AS No. 1,909,525. This arrangement, like various other ones, require a comparatively complex signal transducer apparatus. This signal transducer uses a first signal transducer assembly in which signals are continuously generated by rotating a toothed element, a star wheel, or the like in front of a stationary pickup and, additionally, a second assembly in which a reference marker located to provide a reference signal, determinative of a certain predetermined angular position of the crankshaft. Systems using such transducer arrangements are complex and not suited for mass production in the automotive field, they are expensive and the use of two transducer systems leads to greater susceptibility to trouble or malfunction in comparison to systems in which only a signal transducer is needed.